Grease dispensing device



March 28, 1933. J. H. BECKER. 1,902,822

GREASE DIsrENsING DEVIE Filed Sept. 9, 1926 F' IEE-l la Hronuns Patented Mar. 28, '.1933

UNITED .STA

Tas',

.RATE-NTT oFFlcE.

.Tomos H. BECKER, or SAN FRANCISCO, CamroRNalnssmNoR, RY DIRECT Aim mEsNR AsSIGNMEN'rs-To ALEMITE CoRroRA'rioN, A CORPORATION or DELAWARE GREASE DISPENSING DEVICE .Application filed-September 9, 1928:: serial No. 134,875.

This invention relates generally to devices for discharging 4or .pumping lulds under pressure and has special application as a d1s penser of lubricants.

In the lubrication of motor vehicles 1t has become common practice to use a hand or mtor operated pumping .device w h1ch ma be temporarily connected to a bearing for o rcing in grease at high pressure. Small portable devices of this kind are known as grease guns vand generally comprise a `small high pressure plunger operated by means of a hand lever and mounted upon a chamber for containing a charge of grease. All of these devices operate upon the principle of a simple pump, a relatively small .amount of grease being discharged at every stroke of the plunger although a pressure of several 'thousand pounds per square inch may be attained. Many parts of an automobile.l which must be lubricatedd such as steering gear and transmission housings,- lrequire a relatively large quantity of grease which may be injected at fairly low pressures.- In lubricating devices such as described above, muchetime is lost in lubricating such bearings since the plunger als4 ' vise a grease g must be `given a large number of strokes to discharge the required amount of grease.

It is an object of this .invention'fto construct a device of the class Adescribed which'` `,will either discharge a large quantity of fluid at relatively low pressure or a small quantity at a relatively higli pressure. l

It is a further object of this inventionto construct a device for dispensing lubricants which for a'given cycle-Epi operation will either discharge a large or "smallquantity of lubricant, 'depending upon whether a low or to inject the grease into the bearing .or other mechanism being lubricated. v o

It is a; further object of this inventionto devise a grease gun which may be easily controlled and inwhich the amount of rease in therhamber may be readily gauge It is another object of this invention to de- .having a novel form of linkage onnectingthe hand lever and pump whereby substantially/.no sidetihrust is transmitted 'to the pump plunger and in which the effective lever ratio increases toward the end of the stroke. i

Further objectsV of this invention will appear from the following description in which I have set forth the preferred embodiment 01E` my invention. It is to be understood that the invention is to be'acoorde'd a. range of mechanical equivalents consistent with the state of the prior art.

Figure 1 is a side elevational view of a dispenslng device incorporating the principles of this invention.

Fig.' 2 is a cross sectional elevational view of thev dispensing device shown in Fig. 1.

Fig. 3 is a cross sectional view taken along the line 3 3 ofFig. 2.

Fig. .4 is a cross sectional view taken'along the line 4-4'of Fig. 2.

`The invention comprises generallyl a pumping mechanism which lis adapted to. discharge relatively large quantities of iuid at low pressure or comparatively small quantities at a fairly high pressur corporated in a grease gunlor a dispensing device for lubricants, the pumpin ,mechanism preferably takes the form o at least When 1ntwo pump plungers, one of "large, diameter 1 for discharging grease at low pressure and another of small diameterifor dischar at high pressure. Associated with the plunge eroflarge diameter there is a suitable mech.- anism automatically responsive to the ydischarge pressure `for rendering this plunger ineffective when this discharge pressure 1`n`2 creases to a certain given maximum value.

l After the low pressure plunger is automatically rendered ineffective ,the highvpressure plunger continues tol discharge small quantities of A grease at high pressure "into the bearing.

The particular lform, of dispensing device shown in the drawing comprises a grease chamber l0 which is preferably'cylindrical sins in shape and is adapted to be `secured to a body `member 11 for containing thepump 4mechanism. This body member 11 is pro- 'vided with a dischar e outlet 12 which has been shown as provi ed with a suitable .fitting 13 for attachmentto a flexible hose or otherldischar'ge. pipe. rIhe discharge outlet A member is entra is also provided with a suitable check valve cocmprisin for example -a ball 14 ressed upon a va ve 15 by means of a relativ y softA spring 16.

The um in mechanism for discharging Huid tllrouph the-outlet 12 includes a. lowN pressure p unger 18 which is ada toA snugly fit and reciprocate within a ore 19 provided within the body member 11. A second or high pressure plunger 20, of smaller diameter than thev lunger 18, is also.ar ranged within the y member and is adapted to reci rocate within the bore 21, which bore may formed as a continuation of the 15 discharge outlet 12. The plunger 20 is preferably mounted upon one end of the plunger 18 so that the two Lplungers reciprocate inunison. For convenience in manufacture it is also desirable that these plungers be in 20 alinement so that the bores 19 and 21 for these plungers may also be constructed with. a common axis.l s the two bores may not be constructed with exact accuracy it is also desirable to mount the plunger 20 so that it ma aline itself to compensate for irregu larities in alinement between the bores -19 and 21. This can be accomplished by providing a relatively loose, mounting for the lunger 20; for example, this plunger has been shown as havinga relativelyloose tit within a socket 22 provided in the inner end of the plunger 18, a'locking pin23 extending loosely through both plungers to retain the same together. In order to ermit portions of the grease charge 25 to drawn into the pumpiln mechanism, the 'body member is provi 1 with a suitable port 26 communicating between the linterior of the grease chamber 10 and the interior of the bore 19. -Thisport v is (pslaced intermediate the inner and Quter en vof the bore so that when the plunger 18 is withdrawn a suicientdistanceto ex osethe port, ase from the chamber may ow into the interior of the -body member beneath the plunger 18 and around the pluner 20'. When the plungler 18 is forced inwar v, port 26 is closed 'an grease within'the y ped and forced outwardly 59'. through the disc arge outlet 12. During the latter part of the stroke of plunger 18, pv unger 20 enters bore 21'so that during completion of its movement grease is discharged .onl from bore 21,* 55. en the discharge `of iiuid meets with resistance, as when lu ricating a close'itting bearing, 4the fluid pressure will immediately build up to a value dependingv upon the amount of force bein vvexerted against `the 69 plunger. When this ischar e pressure attains a certainmaximu'm va ue, lbeen provided for' automatically' rendering the low pressure plunger inactive and for only\ the high pressure plunger ce 2'0'to operate to` discharge small quantities a substantial ortion of tachably secured tothe bod n. cup-washer "leather,l which is-secured to -means has filling to return the fluid entrapped in the bore 19 to the chamberlO, or other source 'from which' the fluid is rpumped, the fluid being onl permitted. to bypass when the pressure bui ds up to a certain maximum value.- For example, the body membery has been shownv as rovided with av port 28 communicating wit the inner ortion of the bore 19 and wit the interior o a pressure loperatedvalve 29. -A port 30 leading from this valve 29 permits entrapped iuid in the bore `19 to escape back into the chamber 10 `when the pressure rises above a given maximum value. The particu-y lar form of pressure operated valve showny comprises a ball 32 pressed upon a seat 33 by means of .a compression spring 34, the strength of this spring determining the pressure at which iiuid is permitted to by-pass. In order to facilitatemanufacture it is preferable to center the valve 29 withl respect to the chamber 10, in which case the bre 19 is counterbored at its inner end as at 35 to provide a passageway around the periphery of `the plunger 18 to permit fluid to flow into the port 28.. The length of the high pressure plunger 20 is of coursesuch that it 'does not come into operation within the bore 21 until placed from t e bore 19 y plunger 18. 4

.The particular form of grease chamber shown incorporates many novel features which are applicable to grease` guns in genenal. The innerend of this cha'mberis desuitable means such` as a readed connecgrease has been disthe low pressure e member 11 by tion 37 provided upon theflange 38 entend ing from the body member.

corporated with thisconnection for securing 'an :ai -tight fit. W'thin the chamber therel is arranged a follower 40 which is adapted to rest upon the surface of'la charge 'of ease. This follower is shown as constructs of a 41 of suitable-material such as la guide member inthe form of a metalcu 42,'as by means of screws or bolts 43. -ile with greases of medium viscosityfatmos'pheric air pressure A washer 39 of suitable material such as fiber, maybe inf is suicient to maintain the follower upon the surface of the grease, it is preferable to' prof videv resilient spring means for positively pressing upon the same. Thus between the ollowei and the cap 44 provided upon the' outer end ofthe hamber 10, therel isi asuitf able compressie v spring 46 havingits inner end seated upon a washer 47 4.disposed upon the cup washer 41. v

of provided4 for withdrawing.. the. follower, 40

against the' compression spring 46 without v In order tol provide for the convenientre# the grease. chamber means has been a chain 48 or other articulated member having its inner end secured to the follower as by means of a clevis connection 49, and hav. ing its other end secured to a suitable grip-N pmg device comprisivigla ring 50 secured to a Banged plug. 51. en the grease gun is normally 1n use the ring 50 may be temporarily. attached tothe -cap 44 by means of the plug which is insertable within an aperture 52 provided in the cap. The aperture' 52 is provided with slots 53 for passing the projecting end of a pin 54, this pin being inserted through the plug 51. When the ring 50 and plug 51 are rotated after insertion in the aperture 52, the pin 54 serves as a locking means to retain the ring in this' position. When it-is desired to refill the chamber, the chamber is unscrewed from the body member 11 and inserted open end downward into 29 a reservoir or receptacle containing the 33 generally made substantially the same length as the length of the grease chainber so that when the follower has reached thelimit of its travelI and substantially alll .off the rease has been discharged from the cham- 'er, the chain is practically taut. Therefore at rany time during normal operation of thev device the amount of grease within the chamber may be gauged by unlocking thering from the cap 44 and withdrawing the 40 same from the chamber as indicated in the vdotted lines of Fig-1. The length of the shown as being in the form of amanually by means o chain which may be withdrawn without actually moving the follower v40 will represent approximately the depth of the grease charge remaining in the chamber. The plungers 18 and 20 are reciprocated a suitable'actuator which may be either' motor or manually operated. In this particular case the actuator has been operated lever 56 fulrumed as by means f pivot pin 57 to thevbifurcated outer end of the plungerr 18. This lever is also pivotally connected as by means of pin 58 to adjacent ends of a pair of links 59, the other ends of these links being pivotally connected to the body member llas by means of the pivot pins or screws 60. The'centers of pivot pins 57 .and 60 are substantially alined Hwith the axis of plunger 18. The distance between the pivot pins 57 and 58 is also preferably made relatlvely short compared to the length l.of the links 59, and the centeredlie of the pin is arranged to be substantially at right angles to the center line of the handheld lever ortion61.; With a linkage connection of this Eind practically no side thrust will be exerted against the-plunger 19 throughout the stroke of the hand lever, with the result that a little wear will occur between the reciproeating. parts. Furthermore, vthe effective leverage ratio of the hand lever upon the lunger increases as the plunger advances into the body member so that much greater forces may be exerted against the plunger with a given .force upon the hand lever when the lever is near the end of its stroke and the device is discharging grease by vmeans of the high pressure plunger 20. This effect is made clear b inspection of Fi 1 yin which the full lines show the toggle elgec t obtained when the plunger is near the limit of its inward movement.

To summarize the-operation of the device the o erator actuates the pumping mecha nism Ay oscillating the hand lever 56. Upon movement of this levex` to the outer limit of its travel the plunger 18 is retracted to expose the port26, and since the check valve in the discharge outlet 12 prevents entrance of air or grease into the bore 19, the partial vacuum thus created draws grease. from-the chamber 10 through port 26 into the interior 'of the body member beneath `the plunger 18.

Upon returning the hand lever to its initial position the plunger 18 is forced inwardly to displace grease and force the same through the outlet passageway 12. Assuming first that the discharge of grease meets with little resistance, the valve 29 will remain closed with theyresult that the grease displaced by plunger 18 willl be discharged through outlet 12 rather than be bypassed back into the grease chamber. However, as the plunger.; 18 nears the last part of its movement, plunger 20 enters the bore 21 and displaces the relatively small amount of grease within the same. The entrance of the yplunger 20,'into the Ibore 21 however prevents further V discharge of grease displaced by the plunger 18 with lthe result that A this remainder is' bypassed through valve 29 back into the grease chamber. charge of grease meets with considerable re# sistance, the pressure within the body member will immediately build up upon initial inward movement'of the plunger 18 with the result that substantially all of the grease displaced Aby this plunger will be bypassed.

throughl valve 29 back intol the chamber.

ters the bore 21 a small quantity of grease will Assuming howeveri that `the dis.

be discharged at high pressure during the latter part of the cycle of movement or stroke of the hand lever. In practice the spring 16 of the check valve is made relatively softer than spring 34 of the pressure operated valve 29, the check valve servin only as a means for preventing entrance o, `air or return 'of grease` into the body member. The spring 34 grease as employed in the specification and claims refers to any lubricant whether viscous or free-liowing. f

l. In a dispensing device, a grease chamber, means for discharging grease from one end of said chamber, a follower disposed within the chamber and adapted to rest upon a charge of grease, an articulated member having one of its ends attached to said follower ahd its other end extending Athrough an aperture in the other end of the chamber,

said member being engageable with said end of said chamber at a plurality of points spaced along its length thereby to hold said follower in substantiallyl any desired posiv tio'n within said chamber, means for detachably securing the outer end of said member to the chamber, and spring means for resiliently forcing the follower against the grease. Y

2. In a portable grease .dispensing device i a tubular grease reservoir, a cap therefor, a

passageway extending throu hv said cap, a

plunger comprlsing a pair o concentrically mounted pistons, a bore in said passageway for each of said concentric pistons, an inlet louter end of the smaller of 'sai port in the larger of said bores communicating with said reservoir, a hand lever mounted on said head, adapted to reciprocate said plunger, and a valved discharge outlet at the ores. -3.In\a grease dispensing device a grease (reservoir, a cap for said reservoir compris'-` ing a head, means for automaticallyl feeding the grease in said reservoir' to said head; a passageway extending through said head comprising a large cylindrical bore, a small cylindrical bore, a plunger opel-ably disposed in said passageway comprising a large piston f having a socket in the face thereof and a small discharge stroke.`

piston loosely secured within said socket, a discharge conduit connected to said small bore, saidpistons cooperablewith their respective cylindrical bores to discharge grease therefrom, said large'piston being operable only at the beginnmg of the discharge stroke to discharge grease, said small piston being v small of the pump.

In testimony whereof, I have hereunto set` my hand.

comprisin a large cylindrical bore, a small cylindrica bore, and a chamber disposed betwee'n said bores; a plunger operably disosed in said assageway comprlsing a large lpdiston havingrzil socket in the face thereof and a small piston loosely secured' within said socket a discharge cond-uit connected to said bore, said pistons cooperable with their respective cylindrical bores to discharge grease therefrom, said large piston being operable only until the pressurefin the discharge conduit reaches a predetermined value and a pressure relief valve opening from sai chamber and adjustable to determine the de gree of pressure at which the large piston is rendered ineffective to discharge ease.

5. In a grease dispensing-devlce a grease reservoir, a cap therefor comprising a grease pump and means in said reservoir f or auto- V matically-jfeeding grease to said pump, said pumpn comprising a body member having a plurality o concentric bores extendin therethrough, a discharge outlet for sai Cpump leading from one of said bores, said bores being of different diameters, and a plunger operable within said bores comprising a pair of pistons of dierent diameters, a socket in the face of thel larger of ysaid pistons, the

smaller of said pistons being concentrically secured to said larger piston within said socket, so as to be capable of slight movement relative thereto, said plungers being cooperable with their respective bores to discharge grease from the pump under different -pressures at different periods of a single stroke LJULIUS H. BECKER. l

operable only ,during the latter part of the In a grease dispensing device a grease reservoir,-\a\cap for said reservoir com rising 4 eedmg.

`a head, means )for automatically the grease in said reservoir .to'said head, a passageway lextending 'through said head loo lso f 

